Blue Flag, Poison Flag
Native to the Finger Lakes Region, Eastern Canada, South to PA and Mn.
Strap-shaped leaves and blue-violet flowers on 1-4' tall stalks.
Light: full sun Moisture and Soil: moist to wet
Seed Treatment and Storage: keep seed moist; 60-90 day cold/moist stratification.
Boiled roots were crushed to make a poultice to reduce swelling and bruises and to treat burns and sores.
The butterfly Papilio glaucus visits blue flag iris flowers to suck nectar, but probably does not aid in pollination. Only long-tongued bees, such as bumble bees (Bombus spp.) are efective pollinators. Several beetle species have also been observed on the flowers.
Iris rhizomes and rootstocks contain a purgative irritant, called irisin, iridin, or irisine, that causes gastroenteritis if ingested in large amounts.
Source of plant
North Creek Nurseries, The Plantsmen, Busse Gardens, Jardin Botanique de Montreal, Nolin River Nut Tree Nursery, Sunny Border Nurseries
Narrow gray-green leaves and purplish flowers, borne in early summer. Plants 2' tall, 1' wide.
USDA Hardiness Zone